This invention pertains to adjustable springing mechanisms, particularly those useful for springing vehicle chassis upon running gear under varying loads.
Roadability and driving characteristics of an automobile depend controllingly upon the vehicle being optimally loaded. In the making of an automobile the springing is designed for a particular load range. This optimal load range is in most cases very narrow. But only within this narrow range --more exactly, only in its center-- do the driving characteristics reach their optimum.
For example, in a front-engined passenger automobile which contains only the driver and perhaps one additional passenger, but no luggage or other additional load, the rear of the car will point somewhat upwards, because the rear wheels are too lightly loaded. The cocked attitude of the chassis which this produces impairs the driving characteristics and predisposes to possible skidding. For this reason, many drivers load ballast in the trunk if they are traveling alone or with one passenger.
Automobiles of the luxury class are frequently equipped with air suspension, which the driver may always adjust according to the load and so level the vehicle to the optimal attitude. This leveling may even be effected automatically In the optimal attitude the distance between the chassis and the axle always has the same value, independently of the vehicle load. With such air suspension the amount of load impairs the driving characteristics hardly at all, and the riding comfort not at all.
Such an installation is very expensive and cannot be considered for the large majority of automobiles. But it is precisely small and medium size vehicles in which the defects of prior art springing have the greatest effect, because the ratio of passenger and load weight to vehicle weight is relatively high. Thus for such vehicles and urgent need exists for a possibility of adjusting the springing means, by which the springing may be accommodated to the currently existing load, and the distance between the chassis and the axle may be adjusted to the best value for driving behavior and riding comfort.